1. Field of the Invention
This invention relates to a user interface to control and monitor basic functions of a computer system, and, more particularly, to providing such an interface on a peripheral device to which the computer system is optionally attached without affecting the functionality of the peripheral device when the computer system is not attached thereto.
2. Summary of the Background Art
Typical “desktop” computer systems include a system unit providing basic functions such as a microprocessor, data storage, and various forms of connectivity, together with a number of peripheral devices, which typically always include a display unit and a keyboard, and which often further include a printer, a scanner, and an additional form of data storage. Since the keyboard, pointing device, and display unit provide interfaces that are used throughout typical operation of the computer system, these peripheral devices are generally kept within easy reach of the user. On the other hand, the system unit does not need to provide such interfaces, particularly in an environment in which floppy diskettes, which have traditionally been inserted into a drive within the system unit, are being used with decreasing frequency, with data being more typically transmitted over wired or wireless networks.
The patent literature includes a number of descriptions of methods for providing a user interface at a display device and for transferring control information from the display device to the system unit of a computer system. For example, U.S. Pat. Nos. 6,268,845 and 6,289,466 describe a computer system including a display unit having a universal serial bus (USB) connection as well as a VGA connection with the base system unit. Multiple button and LED controls are conveniently placed on a front bezel of the monitor. As the buttons are actuated, commands are passed to the base system via the USB. An onscreen display button causes an application to be launched on the base system for modifying screen attributes stored in a monitor controller in the monitor. A USB controller in the monitor updates the monitor controller via the USB. A multifunction audio dial is toggled bv a bezel button between volume, bass and treble functions. The USB controller is also operable to provide and sustain a blinking LED even while the base system is in a sleep state, with LEDs on the front bezel indicating monitor and base system power status.
U.S. Pat. No. 6,292,178 describes a display system configured to provide a user interface for use in ophthalmic surgery, with the display system having a screen and a bezel with a generally horizontal shelf aligned with the bottom of the screen and a generally vertical portion aligned with a side of the screen. A plurality of spaced apart switches is disposed on the horizontal shelf, with each switch being provided for activating a corresponding vertical display aligned with the switch on the screen. A sliding touch control panel, disposed in a continuous strip along the bezel vertical portion allows selections of functions and alphanumeric data appearing in a vertical display that can be presented on the screen. A computer attached to the display device is used for generating vertical displays generally parallel to the vertical display.
U.S. Pat. No. 5,483,260 describes a method and apparatus providing bi-directional communication between a video monitor and a computer system unit, without providing an additional user interface at the monitor. This method enables the video monitor to inform the system unit of its capabilities without direct user involvement and also enables the system unit to directly control or adjust all the functions of the video monitor. In the preferred embodiment, bi-directional communication between the video monitor and the system unit is provided utilizing a mouse port in the keyboard controller of the system unit. Multiplexers are coupled between the mouse port and each of the mouse and the video monitor to select between data paths and to selectively allow communications between the system unit and the video monitor.
What is needed is a way to provide for a user interface at a peripheral device, such as a display device, with the user interface providing at least a capability for turning a system unit attached to the display device off and on. Preferably, such a user interface is provided in a way that does not interfere with the use of the display device attached to a system unit not having a capability of being switched off and on in this way. Since such an interface must be capable of turning the system unit on, it should not rely on the execution of programs within the system unit for operation.